Geom-e-Tree - John Miller
Explore fractals with this tree-drawing app for iPod, iPhone, and iPad. Choose the number of branches, angle between branches, and the common ratio of the levels in the tree. See, in particular, the exercises and open questions on Geom-e-Tree for the
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Geometric Factoring - Suzanne Alejandre
A Math Forum Web Unit. Understanding factoring through geometry: students work cooperatively to display a numeral as the area of a rectangle, and make as many rectangular arrangements as possible for each numeral given.
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Geometry Daily - Tilman Zitzmann
A new "geometric minimal composition" every day since January, 2010. Zitzmann, an interaction and graphic designer, "draws simple shapes, combines them and experiments until they start to 'sing,'” then Photoshops them to have the look of "analog paper."
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Geometry Homepage - ThinkQuest 1997
Illustrated tutorials on many aspects of geometry, including: triangular geometry, the Pythagorean Theorem, polygonal geometry, polyhedra, and non-Euclidean geometry. Also includes a list of important geometric formulas.
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Geometry in Motion - Daniel Scher
Direct interaction with geometric diagrams, courtesy of JavaSketchpad. The contents include a variety of curve-drawing devices (Intersecting Circles, Falling Ladder, Van Schooten's Parabola, and more); also other activities such as Constant Perimeter
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Geometry Online - Cynthia Lanius
Geometry activities from a geometry class at Milby High School in Houston, Texas. Topics include: History of Geometry (contributions of Egyptians, Babylonians, and Greeks, with links to biographies of major contributors to geometry); Hidden Polygons (locate
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The Goal Angle Problem - Ken Koedinger
Two solutions to the following problem: as you are running down a soccer field with the ball, when is the angle subtended by the goal at its maximum? There is also a sketch illustrating a construction used in one of the solutions (quadrature of the rectangle).
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Imaging the Imagined - Paul Flavin
Modeling with Math and a Keyboard: the art and science of modeling; the math, theory and practice of rendering, imaging, and animation. An introduction to raytracing and the Quadric surfaces; Platonic Solids and Polyhedra; 'Tensegrity' (tension) structures;
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Investigating Polygons - Margo Lynn Mankus
The lesson plan for What is the Sum of My Angles? has the objectives of investigating the sum of the measure of the interior angles of a triangle using several methods, and making a mathematical conjecture from observations. The lesson plan for Regular
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Investigations in Mathematics - Eric S. Rowland
Open-ended problems for high school and college students to "approach creatively and in their own way": Pascal's simplices ("What is the generalization of Pascal's triangle?"), Pythagorean triples, regular polygons ("What is the area of a regular polygon
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Isotiles - John Everett
Isotiles are specially designed tiles, in just two triangular shapes, by
which a wide range of topics in geometry can be studied. Topics include: different types of angles; lines and angles; angles of a triangle; isosceles triangles; similar triangles;
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Kirigami - Kevin S. Whitley
Kirigami is the Japanese art of making figures out of paper by cutting. This applet lets you create similar figures on your computer by cutting a polygonal wedge from a virtual piece of folded paper. You can change the regular polygon, your wedge, and
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KRN Software
Free online games for Java-enabled browsers. Java Edutainment games require matching shapes and colors in Space Cargo and Cargo Bay, simple addition in Numeric Defenders, and odd and even number identification in Even Steven, Jr.
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Learning Jolt - Robert Croisant
"Quick and repeatable" mathematics problems for students, who gain points at specific milestones which they may then use to choose their own rewards in the Learning Jolt store. With statistical reports and other tools for parents and teachers to track
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Learn Math 3D on Orbital One - Peter Richards
A software math course set within a real time 3D environment. Topics covered include counting, the number system, addition, subtraction, multiplication, division, 2D and 3D shapes, simple fractions, and telling the time.
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